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71.
Ulrich Tibes Edeltraud Haberkorn-Butendeich Frithjof Hammersen 《Pflügers Archiv : European journal of physiology》1977,368(3):195-202
Summary The effect of muscle contraction on lymphatic and plasma [K+], [Na+], [Ca2+], [Mg2+], [Cl–], [Pi], [lactate] ([Lac–]); [creatine] ([Cr]), ideal osmolality (OSM), and [protein] was evaluated in femoral venous blood and lymph specimens sampled from the calf muscles of rabbits before, in the course of, and after contractions. In addition, total [K+], [Na+], [Ca2+], [Mg2+], [Cl–], and [H2O] were analyzed in the muscle tissue. To facilitate lymph sampling both hind limbs were passively flexed and extended, in imitation of natural running movements, by an electrically driven crank. The muscles of one side also performed superimposed rhythmic isotonic contractions. Before contractions, lymphatic [K+], [Na+], [Ca2+], [Mg2+], [Lac–], [Cr], and OSM did not significantly differ from corresponding femoral venous concentrations, [Cl–], and [Pi] were significantly higher, [protein] significantly lower in the lymph than in the plasma. During contractions lymphatic [K+], OSM, [Lac–], and [Pi] were raised significantly more in the lymph compared with the plasma concentrations. [Na+], [Cl–], [Ca2+], and [Mg2+] showed only small changes in the course of contractions and thereafter, and they were altered in a similar way in the lymph and plasma. It was suggested that lymphatic and interstitial concentrations were in equilibrium. Comparing inactive with active muscles, the latter lost K+ but gained Na+, Cl–, and H2O, whereas minimal changes occurred in the [Ca2+] and [Mg2+]. The changes were discussed in connection with the hypothesis that electrolyte shifts might be involved in the activation of the muscular non-proprioceptive interstitial nerve endings which appear to play a role in reflexogenic cardiovascular and respiratory control.A preliminary report of this work has been given elsewhere [33]Supported by Deutsche Forschungsgemeinschaft 相似文献
72.
Joachim Böttcher M.D. Alexander Pfeil Anders Rosholm Ph.D. Max-Ludwig Schäfer Ansgar Malich M.D. Alexander Petrovitch M.D. Bettina Seidl Gabriele Lehmann M.D. Hans-Joachim Mentzel M.D. Gert Hein M.D. Gunter Wolf M.D. Werner A. Kaiser M.D. M.S. 《Journal of digital imaging》2006,19(3):279-288
Purpose Our study evaluates digital x-ray radiogrammetry (DXR) and Radiogrammetry Kit (RK) as a new diagnostic method for the measurement
of disease-related osteoporosis including quantification of joint space narrowing dependent on the severity of rheumatoid
arthritis (RA).
Materials and Methods A total of 172 unselected patients with RA underwent computerized measurements of bone mineral density (BMD) and metacarpal
index (MCI) by DXR, as well as a semiautomated measurement of joint space distances at the metacarpal–phalangeal articulation
(JSD-MCP 2–5), both were analyzed from plain radiographs of the nondominant hand.
Results Correlations between DXR-BMD and DXR-MCI vs. parameters of RK were all significant (0.34 < R < 0.61; p < 0.01). An expected negative association was observed between RK parameters and the different scoring methods (−0.27 < R < −0.59). The maximum relative decrease in BMD vs. MCI as measured by DXR between the highest and lowest RA severity group
was −27.7% vs. −27.5% (p < 0.01) for the modified Larsen Score, whereas the minimal value of relative DXR-BMD and DXR-MCI reduction could be documented
for the Sharp Erosion Score (−20.8% vs. −26.8%; p < 0.01). The relative reduction of mean JSD-MCP using RK significantly varied from −25.0% (Sharp Erosion Score) to −41.2%
(modified Larsen Score). In addition, an excellent reproducibility of DXR and RK could be verified.
Conclusion DXR in combination with RK could be a promising, widely available diagnostic tool to supplement the different scoring methods
of RA with quantitative data, allowing an earlier and improved diagnosis and more precision in determining disease progression. 相似文献
73.
目的 明确颈深筋膜的分层及筋膜间隙的位置、毗邻 ,为颈深筋膜间隙的影像识别与分析提供参考 ,为临床诊治感染蔓延、肿瘤侵润提供解剖学依据。 方法 采用低温冰冻和生物塑化技术用 17例标本 ,制作了颈部连续薄层横断面 ,对颈深筋膜及筋膜间隙进行了观测。从颈部薄层塑化断面标本上 ,用双线提取间隙轮廓的方法 ,在SGI工作站上对颈深筋膜间隙进行三维重建。 结果 1.颈深筋膜应分为四层 ,颈深筋膜深层分为翼筋膜和椎前筋膜 ,颈深筋膜各层均参与颈动脉鞘的形成。 2 .颈动脉间隙是一开放的间隙 ,其后外侧与颈后间隙相通 ;证实了危险间隙的存在。 3.重建出咽后间隙、颈动脉间隙和内脏间隙的三维图像 ,并能同时显示间隙内的主要结构。结论 得出了颈深筋膜和筋膜间隙的模式图 ,并为筋膜间隙的三维重建提供了一种新的方法。 相似文献
74.
眉部运动的显微外科解剖学研究及其临床意义 总被引:8,自引:0,他引:8
目的:为解决除皱术中眉毛上提效果欠佳,不够持久的问题。方法:对10例新鲜尸体进行了大体及显微解剖。结果:证实了额肌深面“滑动层”和“滑动间隙”的存在,观察了眉内侧2/3自皮肤向深面发出固定到眉嵴处的眉毛支持韧带,外侧上方的颞融合线和下方的眉限制韧带静态固定结构,上述结构决定了眉毛的形态;阐述了额肌、皱眉肌和降眉肌的眉毛动力机制,探讨了老年性外侧眉毛下垂主要由于外侧的滑动脂肪垫向下“疝出”所致。结论:通过破坏“滑动间隙”,切断颞融合线和眉限制韧带,切除外侧滑动脂肪垫,达到眉部上提的良好、持久效果。 相似文献
75.
Activity-related changes in extracellular K+ concentration ([K+]e), pH (pHe) and extracellular volume were studied by means ofion-selective microelectrodes in the adult rat spinal cord in vivo and in neonatal rat spinal cords isolated from pups 3–14 days of age (P3–P14). Concomitantly with the ionic changes, the extracellular space (ECS) volume fraction (α), ECS tortuosity (λ) and non-specific uptake (k′), three parameters affecting the diffusion of substances in nervous tissue, were studied in the rat spinal cord gray matter. In adult rats, repetitive electrical nerve stimulation (10–100 Hz) elicited increases in [K+]e of about 2.0–3.5 mm, followed by a post-stimulation K+-undershoot and triphasic alkaline-acid-alkaline changes in pHe with a dominating acid shift. The ECS volume in the adult rat occupies about 20% of the tissue, α = 0.20 ± 0.003, λ = 1.62 ± 0.02 and k′ = 4.6 ± 0.4 × 10−3s−1 (n = 39). In contrast, in pups at P3–P6, the [K+]e increased by as much as 6.5 mm at a stimulation frequency of 10 Hz, i.e. K+ ceiling level was elevated, and there was a dominating alkaline shift. An increase in [K+]e as large as 1.3–2.5 mm accompanied by an alkaline shift was evoked by a single electrical stimulus. The K+ ceiling level and alkaline shifts decreased with age, while an acid shift, which was preceded by a small initial alkaline shift, appeared in the second postnatal week. In pups at P1–P2, the spinal cord was X-irradiated to block gliogenesis. The typical decrease in [K+]e ceiling level and the development of the acid shift in pHe at P10–P14 were blocked by X-irradiation. Concomitantly, continuous development of glial fibrillary acidic protein positive reaction was disrupted and densely stained astrocytes in gray matter at P10–P14 revealed astrogliosis.The alkaline, but not the acid, shift was blocked by Mg2+ and picrotoxin (10−6m). Acetazolamide enhanced the alkaline but blocked the acid shift. Furthermore, the acid shift was blocked, and the alkaline shift enhanced, by Ba2+, amiloride and SITS. Application of glutamate or gamma-aminobutyric acid evoked an alkaline shift in the pHe baseline at P3–P14 as well as after X-irradiation. The results suggest that the activity-related acid shifts in pHe are related to membrane transport processes in mature glia, while the alkaline shifts have a postsynaptic origin and are due to activation of ligand-gated ion channels.At P4–P6, the ECS volume was almost double that in adult rats, α = 0.37 ± 0.01 (n = 17), the ECS tortuosity was significantly higher, λ = 1.78 ± 0.02, while the non-specific uptake was not significantly different, k′ = 3.61 ± 0.56 × 10−3 s−1. The α gradually decreased to about 24% at P12. In adult rats, electrical or adequate stimulation evoked a shrinkage of the extracellular space by 20–50%, while no significant changes in ECS volume were found in P3–P6. We conclude that the [K+]e ceiling level, character of the pHe transients, the size of the ECS volume and the activity-related ECS shrinkage are closely related to gliogenesis. 相似文献
76.
The relationships between muscle size, diffusion distance, and glucose uptake were studied using the Type II b epitrochlearis (13 ± 1 mg intact), Type I soleus (25± 1 mg), and mixed Type II a/II b extensor digitorum longus (25 ± 1 mg) from 60–70 g rats. Using intact muscles, the relative rates of 3-O-methyl-glucose uptake in response to 2 mUml-1 insulin were soleus = epitrochlearis > extensor digitorum longus, a finding inconsistent with the fibre-type compositions and the relative GLUT-4 protein levels (soleus > extensor digitorum longus > epitrochlearis). To test whether these results were influenced by substrate diffusion limitations in the tubular muscles, soleus and extensor digitorum longus were split longitudinally from tendon to tendon into strips of comparable size (13 ± 1 mg) to the epitrochlearis. Insulin-stimulated rates of 3-O-methyl-glucose uptake were significantly enhanced in the split soleus (+120%) and split extensor digitorum longus (+200%), but not in the epitrochlearis, with the relative rates being soleus > extensor digitorum longus > epitrochlearis. Diffusion distances of the split soleus and extensor digitorum longus, as reflected by [14C]mannitol space equilibration time, were markedly enhanced (by at least 50%) relative to the intact muscles, and were comparable to that of the epitrochlearis. These results indicate that when muscles of different size and/or shape are used for in vitro measurement of glucose transport, the muscle preparations used must have similar diffusion distances for physiologically meaningful comparisons to be made. 相似文献
77.
Elisabet Kaa 《International journal of legal medicine》1987,99(2):87-94
Summary Hundred thirty-eight samples of heroin weighing more than 0.1g seized between 1981 and 1986 were characterized according to their contents of opium alkaloids, adulterants, and diluents together with their form and color. The chemical fingerprint was used to establish a change in the heroin during the period. As compared to the first few years covered by the survey, a predominant number of the samples at the end of the period were in the base form and contained the opium alkaloids papaverine and noscapine. In particular, the concentration of noscapine as related to the heroin content of each sample had increased considerably, indicating Pakistan or Iran as being the places of origin of most of the heroin seized in Denmark at the end of the period. 相似文献
78.
M. Imbriani S. Ghittori G. Pezzagno E. Capodaglio 《International archives of occupational and environmental health》1984,55(1):33-41
Summary The concentration of n-hexane in urine was determined in 30 subjects occupationally exposed to n-hexane (median value 59.6 mg/m3) in a shoe factory. The measurement of the substance was performed by means of a Hewlett-Packard 5880 gas chromatograph supplied with a Hewlett-Packard 5970 Mass Selective Detector. The analyses were performed by the head space method (constant volume method, after determination of the urine partition coefficient by the multiple phase equilibration method). The authors found a significant correlation between the n-hexane urine concentrations (g/1, Cu) and the n-hexane environmental concentrations (mg/m3, Ci) (r = 0.84; Cu = 0.0669 x Ci + 0.8396).This work was supported by the research funds given to Fondazione Clinica del Lavoro, Pavia by the Health Council 相似文献
79.
【目的】 探索现有条件下我国建设化学专业刊群的有效方式和途径,为我国专业期刊集群建设和期刊发展提供经验和借鉴。【方法】 以中国化学会期刊集群的建设为主要研究对象,分析总结在我国期刊发展现有环境下化学专业刊群建设的现状、存在的问题、解决方案和启示。【结果】 中国化学会通过专业期刊集群建设、数据整合,为我国化学工作者提供丰富的学术资源,为国产优质化学期刊提供一个重要的展示、合作平台,但在规模、学术质量、运营方面仍有很大差距,还需进一步提高建设水平。【结论】 专业刊群建设应勇于突破固有观念屏障,以优质数据资源为基础,充分发挥集群优势,构建期刊协同发展格局,为我国相关专业学科发展作出应有的贡献。 相似文献
80.
〔摘 要〕 益智仁为姜科山姜属植物益智的干燥成熟果实,是我国著名的四大南药之一,在临床上常用于治疗腹泻、尿频、
炎症以及癌症等疾病。近年来,对益智仁的药理研究主要在其提取物和化学成分上,本文作者综述了其在腹泻、阿尔茨海
默病(AD)、癌症、肾病、骨疾病等方面的研究,为以后对益智仁的研究、开发与应用提供了基础。 相似文献